Acecow, try wandering around Monmartre along Rue Abbesses near Rue Lepic. There are some reasonable local cafes. When you have finished dinner walk down to Blanche Metro. Get on Bus 30 heading west. This goes via the Arc to the Trocadero. From Trocadero there is a great view of the tower lit up in the dark. Then it is a nice walk down to the river.

From what I see the first look isn't bad. As for the 2nd look, if you are going to wear a blazer/sport coat casually you might wanna go with one that is unconstructed. That looks like an orphaned suit jacket

the third look has too many issues. If you are going to wear a vest solo ever you should never have it unbuttoned (Unless it's the last one). As for the tie loosening it up like that makes it look like you are wearing a chain. A four in hand tie knot would also look better on you. If you would like a thicker knot (Which I don't think you need since you have pretty slim proportions) you should try at most a half windsor knot.